PCB Board Design Assistance for Ceramic Capacitor Crack Reduction

Solution Overview

Problem

The challenge is to reduce the likelihood of cracks in ceramic capacitors on printed circuit boards, especially with smaller chip sizes, while maintaining flexibility in electronic component layout, as existing crosswise routing techniques may limit design flexibility and increase stress on capacitors.

Innovation Solution

A board design assistance device that includes a design data acquirer, a first determiner to check if the board fiber direction is perpendicular to the ceramic capacitor's longitudinal direction, and a second determiner to verify if wires are routed crosswise from the pads, providing notifications for designs that do not adhere to these stress-reducing structures.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If crosswise routing is used to reduce cracks in ceramic capacitors, then reliability is improved, but layout flexibility deteriorates

Engineering Contradiction:

Improvelikelihood of cracks in ceramic capacitorVSAvoidlayout flexibility

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The system performs preliminary analysis of capacitor orientation and wire routing before finalizing the PCB layout. By checking whether wires are routed crosswise relative to the board fiber direction and whether the capacitor's longitudinal direction is perpendicular to the fiber direction in advance, the system can identify potential crack risks before manufacturing, allowing designers to make corrective adjustments without compromising layout flexibility.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system provides feedback to designers by analyzing the PCB design data and notifying them when capacitors are oriented or routed in ways that increase crack likelihood. This feedback mechanism allows designers to maintain layout flexibility while being informed of reliability concerns, enabling them to make informed decisions about whether to adjust the layout or accept the risk.

Inventive Principle:

Principle #23Feedback

2Productivity

If smaller chip ceramic capacitors are used to increase packaging density, then productivity is improved, but stress on capacitors increases

Engineering Contradiction:

Improvepackaging densityVSAvoidstress on ceramic capacitor

Core Design Contradiction:

ProductivityVSStress or pressure

Solution Approach 1:

The system performs preliminary analysis of capacitor orientation and wire routing before finalizing the PCB layout. By checking whether wires are routed crosswise relative to the board fiber direction and whether the capacitor's longitudinal direction is perpendicular to the fiber direction in advance, the system can identify potential crack risks before manufacturing, allowing designers to make corrective adjustments without compromising layout flexibility.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system analyzes and controls critical parameters including the orientation angle between capacitor longitudinal direction and board fiber direction, and the routing direction of wires relative to the capacitor. By optimizing these parameters (ensuring perpendicular orientation and crosswise routing), the system reduces stress on small capacitors while maintaining high packaging density.

Inventive Principle:

Principle #35Parameter changes

3Ease of manufacture

If wider patterns are used to connect smaller pads, then ease of manufacture is improved, but stress on capacitors increases

Engineering Contradiction:

Improvepattern connectionVSAvoidstress on ceramic capacitor

Core Design Contradiction:

Ease of manufactureVSStress or pressure

Solution Approach 1:

The system introduces board fiber direction as an intermediary factor in the design analysis. By considering the fiber direction when determining optimal capacitor orientation and wire routing, the system creates a design that accounts for the board's structural characteristics, allowing wider patterns to be used without excessively increasing stress on capacitors.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The system analyzes and controls critical parameters including the orientation angle between capacitor longitudinal direction and board fiber direction, and the routing direction of wires relative to the capacitor. By optimizing these parameters (ensuring perpendicular orientation and crosswise routing), the system reduces stress on small capacitors while maintaining high packaging density.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS11716817B2Board design assistance device, board design assistance method, and recording medium

Publication Date: 2023.08.01 MITSUBISHI ELECTRIC CORP

AI summary

A board design assistance device includes a design data acquirer to acquire design data for a printed circuit board, a first determiner to determine, based on the design data for the printed circuit board, whether a lengthwise direction of board fiber in the printed circuit board is perpendicular to a longitudinal direction of an electronic component mounted on the printed circuit board, a second determiner to determine, based on the design data for the printed circuit board, whether a wire is routed crosswise from a pad receiving the electronic component mounted on the printed circuit board, and a notifier to provide a notification including error information specifying an electronic component determined to have a longitudinal direction not perpendicular to the lengthwise direction of the board fiber and determined to be connected to a pad from which a wire is not routed crosswise.